Marking device

ABSTRACT

It is an object to provide a marking device which efficiently reduces damage affecting the gimbal mechanism even when it is used under sever conditions and it is dropped from the high location. A marking device has a support  2  mounted inside a housing  1 , a light source unit holder swingably suspended by the support  2  through a gimbal mechanism  3 , and a light source unit  5, 6  mounted on this light source unit holder  4  so as to diffuse a light flux only in a single direction to radiate line light. The support  2  is coupled with said housing  1  through dampers  7, 8  with upper portion and lower portion formed of impact absorber, and when outside impact is applied, the damper absorbs impact energy to prevent the impact force from transmitting to the support  2.

FIELD OF THE INVENTION

The present invention relates to a marking device irradiating verticalor horizontal line laser to a surface of the subject to be irradiated bydiffusing light flux only in a single direction from a light source suchas semiconductor laser, particularly related to its impact absorptionstructure.

RELATED BACKGROUND OF THE INVENTION

In a construction site, used is an optical marking device irradiating avertical line light or a horizontal line light which is a criterion of avertical degree and a horizontal degree of pillars and walls. Most ofthe light sources of the optical marking device are semiconductor lasersand are generally called as a laser marking device. The laser markingdevice suspends a mechanism called gimbal mechanism or a gyro mechanism(hereinafter referred to as “gimbal mechanism”) in the condition ofperpendicular so as to always hold a vertical position and supports alight source unit including the semiconductor laser with the abovementioned light source unit holder. The light source unit includes asemiconductor laser as a light source, a collimating lens convertingdispersing lights radiated from the semiconductor laser into a parallellight flux, and a rod lens dispersing the parallel flux in a singledirection. The parallel light flux is entered into the rod lens from adirection perpendicular to its center axis and diffused in a fan shapeonly in a direction perpendicular to the above mentioned center axis byrefraction with the rod lens. This diffusion light is irradiated towalls, ceilings, and floors of the building to draw straight lines bylight. Then a vertical line light can be irradiated by mounting theabove mentioned light source unit on the above mentioned unit holder insuch way that the center axis of the rode lens is horizontal. And ahorizontal line light can be irradiated by mounting the above mentionedlight source unit on the above mentioned unit holder in such way thatthe center axis of the rode lens is horizontal. This is a fundamentalprinciple of the laser marking device.

In the laser marking device, the light source unit holder supporting thelight source unit is swingablly supported by the gimbal mechanism. Thelaser marking device is required to accurately irradiate lights ofvertical or horizontal direction line. For that reason, the gimbalmechanism is desired to have low friction resistance and the lightsource holder is desired to keep in a predetermined vertical directionposition. Therefore, generally a bearing portion of the gimbal mechanismmainly comprises a ball bearing and an axis rotatably supported thereby.However, since the possibly lowest friction resistance one is selectedfor the ball bearing employed in the gimbal mechanism of the lasermarking device, there is a problem of impact resistance. Therefore, evenin the case that the laser marking device is erroneously fallen downduring use, the bearing portion is damaged due to impact resistance toincrease the friction resistance so that the light source unit holdercannot hold the predetermined position, which causes a problem ofdeteriorated accuracy of the irradiated line light.

Then, proposed is a laser marking device comprising a first support forswingably journaling a laser beam irradiating device with a firstsupport shaft, a second support for swingably journaling this firstsupport with a second support shaft perpendicular to the first supportshaft, and a supporting member provided with a holding portion forholding the second support, wherein the second support is held on theabove mentioned holding portion in such way that interference bodies areinterposed in respective both sides along longitudinal, lateral andvertical directions of the second support (ref. to, for example, PatentReference 1) . The above mentioned “laser beam irradiation device” isthe member corresponding to “light source unit holder”. The firstsupport shaft, the second support shaft and the second support comprisea gimbal mechanism. The above impact absorber reduces impact applied tothe above mentioned holding portion to transmit to the light source unitholder which is swingably journaled by the above mentioned gimbalmechanism, thereby providing the gimbal mechanism with less damage.

The invention of the Patent Reference 1 is effective to protect thegimbal mechanism when the laser marking device is dropped. However, theconfiguration of the above mentioned impact absorber of the PatentReference 1 invention is required to entirely cover the exteriorsurface, top and bottom surfaces, and both side surfaces of the secondsupport, which therefore increases an area and a volume of the impactabsorber and then increases the cost of the impact absorber. And avolume of the laser marking device also increases due to the presence ofthe impact absorber. And there are many subjects to be interfered, suchas the gimbal mechanism, the light source unit holder as well as thesecond support, for which impact absorbing effect should be improved.This is also one of factors to increase a volume of impact absorber.

[Patent Reference 1] Japanese Patent 2004-301756 A

Then, the present inventor proposes a marking device in which an impactabsorber held by a support covers periphery of both ends of a shafthaving a gimbal mechanism and above mentioned shaft is supported by thesupport through this impact absorber. That is an invention related toJapanese Patent Application 2005-64234.

According to the invention related to the above mentioned application,impact absorption effect is provided as expected. However, assuming thatit is used under the severe conditions of drop from high location e.g.more than 1 m, it is found that even the invention related to the abovementioned application can not obtain a sufficient impact absorptioneffect.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a marking device whicheffectively reduces damage of the gimbal mechanism even when it is usedunder sever conditions and dropped from the high location, and which isdurable for subsequently continuous usage.

A marking device related to the present invention comprises a supportmounted inside a housing, a light source unit holder swingably suspendedby this support through a gimbal mechanism, and a light source unitmounted on this light source unit holder so as to diffuse a light fluxonly in a single direction to radiate line light, wherein abovementioned support is coupled with above mentioned housing through damperwith upper portion and lower portion formed of impact absorber, and whenoutside impact is applied, above mentioned damper absorbs impact energyto prevent the impact from transmitting to above mentioned support.

Above mentioned damper has a hole in an axis direction and a smalldiameter portion in a middle portion in an axis direction, the abovementioned hole is penetrated at one end by a mounting shaft coupled withthe housing or the support and the damper is coupled with the support,and the above mentioned small diameter portion is fit in with a portionsubstantially integrated with the support or the housing so that anupper portion and an lower portion of the support are coupled with thehousing through the dampers.

The support is in such form that the lower portion is supported by thehousing through the damper and the upper portion is suspended by thehousing through the damper. Therefore, the support is raised from thehousing by interference of the damper. When the marking device is felldown or dropped, most of the impact force applied to the housing isabsorbed by the dampers in the upper portion and the lower portion ofthe support so that the impact force is prevented from transmitting tothe support. For this reason, the impact force transmitted from thesupport to the gimbal mechanism is reduce and the impact force appliedto the support portion of the shaft constituting the gimbal mechanism isalso reduced, so that damage affecting the gimbal mechanism isdramatically reduced. Even if relatively big impact force is applied,the device can be continuously used without readjustment and repairs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross section of a marking device according to oneembodiment of the invention;

FIG. 2 is a front cross section of the marking device;

FIG. 3 is a schematic top plan view showing an arrangement relating ofdumpers in the upper and lower portions in the embodiment;

FIG. 4 is a front view of the dumper;

FIG. 5(a) is a top plan view of a mounting member;

FIG. 5(b) is a cross section of the mounting member;

FIG. 6(a) is a front view of a sleeve;

FIG. 6(b) is a top plan view of the sleeve; and

FIG. 6(c) is a cross section of the sleeve.

DESCRIPTION OF THE PREFERRED EMBODIMENT

An Embodiment of the marking device related to the present inventionwill be described with reference to drawings hereinafter.

In FIGS. 1 to 3, a cylindrical housing 1 has a top plate 11 and a bottomplate 12, and a lower surface of the bottom plate 12 is mounted with atripod, which is not shown, so as to be installed with the tripod in avertically standing posture. In the housing 1 mounted is a support 2 forswingably supporting a light source unit holder 4. The present inventionfeatures a structure of mounting this support 2. The support 2 iscoupled with above mentioned housing 1 through dampers 7 and 8 formed ofimpact absorber at upper and lower portions. The upper dampers 7 areformed in a pair and each of the dampers 7 is mounted on the lowersurface of the housing 1 with a screw 17. The lower dampers 8 are formedin a pair and held by a diskform mounting member 10 horizontally fixedto inner periphery of the housing 1 in the vicinity of the bottom plate12 of the housing 1. As shown in FIG. 3, assuming that a line connectingcenters of the lower dampers is X direction line and a line connectingcenters of the upper dampers is Y direction line, the above mentioned Xdirection line and Y direction line crosses at right angles with eachother with respect to the center axis of the housing 1.

Each of the above mentioned dampers 7 and 8 has the same structure andFIG. 4 shows a structure of the damper 7 representing these dampers. InFIG. 4, the damper 7 is entirely formed of impact absorber and thedamper 7 has an axial direction hole 71, a small diameter portion 74around an outer periphery of axially center portion, and large diameterportions 72, 73 sandwiching the small diameter portion 74. The impactabsorber forming the damper 7 has a characteristic in which an appliedkinetic energy is absorbed by converting into thermo energy and isrequired to have no repulsion force or low repulsion force. There is“low repulsive rubber” as a material to meet the requirement and spongylow repulsive rubber is used in this embodiment. The above mentionedhole 71 is penetrated by a mounting shaft and one end of the mountingshaft is coupled with the above mentioned housing 1 or the abovementioned support 2, so that the housing 1 is coupled with the support 2with the above mentioned damper 7 interposing there between. Sincestructures in which the housing 1 and the support 2 are coupled with thedamper interposed are different between the upper portion and the lowerportion, the structure of coupling the housing 1 and the support 2 willbe individually described next with respect to the upper portion and thelower portion.

In FIGS. 1 and 2, an extension mounting member 9 is extended to theupper end of the support 2 by appropriate means such as a screw cramp.In the extension mounting member 9, an upper end portion and a lower endportion of a vertical plate are bent at a right angle in a form oflateral U shape. And a piece bent at the lower end of the mountingmember 9 is coupled with the upper end of the support 2. The piece 91bent at the upper end of the extension mounting member 9 is formed withtwo arc cuts, on each of which the small diameter portion 74 of theabove-mentioned damper 7 is fit, thereby mounting the damper 7 on theextension mounting member 9 substantially integrated with the support 2.The hole 71 of each damper 7 is inserted with a sleeve 80 shown in FIG.6. In FIG. 6, the sleeve 80 includes a cylindrical body portion fit inthe center hole of the damper 7, and a flange portion 81 integrallycontinued with one end of the body portion. The center hole 71 of theabove mentioned damper 7 is fit with the body portion of the sleeve 80,and the flange portion 81 of the sleeve 80 is adjacent to the upper endface of the damper 7. A screw 17 penetrating the top plate 11 of thehousing 1 passes through the center hole of the body portion of thesleeve 80 from the upper side, and each screw 17 projected from thelower end face of each damper 7 is fit with a washer 76 and furtherscrewed with a nut. Thus each damper 7 is mounted on the top plate 11 ofthe housing 1 and the upper portion of the support 2 is coupled with thelower face side of the top plate 11 through each damper 7.

FIG. 5 shows the mounting member 10 fixed to the lower portion of thehousing 1. As shown in FIG. 5, the mounting member 10 is formed out of aplane plate material into a ring shape, is provided with four mountingholes 101 circumferentially equally spaced at periphery of the mountingmember 10, and has two round holes 102 for mounting the damper 8. Themounting member 10 also has a relatively big round hole 103 at thecenter of thereof. The mounting member 10 is sandwiched at the lowerportion of the housing 1 and a screw 13 penetrating the above mentionedmounting hole 101 from the lower portion of the housing 1 is tightenedand fixed to the body of the housing 1. The above mentioned two roundhole 102 of the mounting member 10 is fit with the small diameterportion each of the dampers 8, thereby mounting the damper 8 on themounting member 10 substantially integrated with the support 2. Thecenter hole of each damper 8 is inserted with the body portion of theabove mentioned sleeve 80 from the upper side, and the flange portion 81of each sleeve 80 is adjacent to the upper end face of the damper 8. Thescrew 15 is screwed in the center hole of each sleeve 80 from the lowerside, and the upper end portion of each screw 15 projected from theupper end face of each sleeve 80 is screwed into the bottom plate 26 ofthe support 2. A washer 86 is interposed between the top portion of eachscrew 15 and the bottom face of the damper 8 present. Thus each damper 8is coupled with the mounting member 10 substantially integrated with thehousing 1, and the lower portion of the support 2 is coupled with themounting member 10 substantially integrated with the housing 1 througheach damper 8.

Thus, the upper portion of the support 2 is coupled with the top plateof the housing 1 through dampers 7 in such mode that the top plate ofthe housing 1 suspend the support 2, and the lower portion of thesupport 2 is coupled with the lower portion of the housing 1 through thedamper 8 and the mounting member 10 in such mode that the support 2 issupported upward from the lower portion of the housing 1. When impact isapplied in vertical direction in a standing posture as shown in FIGS. 1and 2, the support 2 tends to cause relative movement to the housing 1in vertical direction. At this time, the large diameter portions 72, 73of both ends of the damper 8 in vertical direction are deformed and thelarge diameter portions 82, 83 of both ends of the damper 7 in verticaldirection are deformed, so that each damper 7, 8 converts impact forceinto thermal energy to reduce the impact force transmitted to thesupport 2. When the impact force is laterally applied due to theexternal factor such as fall of the housing 1 in FIGS. 1 and 2, thesupport 2 tends to cause relative movement to the housing 1 in verticaldirection. In this case, the small diameter portion 74 of each upperdamper 7 is pushed by the bent piece 91 of the extension mounting member9 integrated with the support 2, and the small diameter portion of eachlower damper 8 is pushed by the mounting member 10 integrated with thehousing 1. Since the small diameter portion of each damper 7, 8 is alsoformed of absorber material such as low repulsive rubber, the impactforce to be transmitted to the support 2 is converted into thermalenergy due to deformation of the small diameter portion of each damper 7and 8 to reduce the impact force transmitted to the support 2.

The center hole of each damper 7, 8 is fitted with the sleeve 80 andeach damper 7, 8 can deform along a circumference of the sleeve 80,thereby each damper 7, 8 is deformed smoothly and damping function isefficiently performed.

The dampers 7, 8 each may be entirely and integrally formed of an impactabsorber made of the same material. Since the impact force to be reducedis different in direction between the large diameter portion and thesmall diameter portion, different materials may be used so that theimpact force is efficiently reduced based on the direction of the impactforce to be reduced. In the case of different materials between thelarge diameter portion and the small diameter portion, differentmaterials are arranged along the axial direction and adhered.

Next, the configuration of the light source unit holder 4 supported bythe above mentioned support 2 and the gimbal mechanism 3 swingablysuspending this light source unit holder 4 will be described. In FIGS. 1and 2, a pair of bearing holders 21, 21 are integrally formed in theupper portion of the support 2. A pair of the bearing holders 21, 21 hasa cylindrical shape with bottom and open ends are opposing with eachother. And the damper 22, 22 having cylindrical shape with bottom areembedded inside the bearing holders 21, 21. Each damper 22, 22 may beformed of the material having absorption function, such as the impactabsorber made of low repulsive rubber as well as in the above mentioneddamper 7, 8. Bearing 23, 23 such as a ball bearing is fit in the bearingholder 21, 21 through each damper 22, 22, and a shaft 25 is rotatablysupported by the bearing 23, 23.

A intermediate swinging frame 40 is swingably supported around the abovementioned shaft 25. The intermediate swinging frame 40 is integrallyformed with a pair of bearing holders 45, 45. Each of the bearingholders 45, 45 has a cylindrical shape with bottom and open ends areopposing to each other. The damper 44, 44 having a cylindrical shapewith bottom is embedded inside each bearing holder 45, 45. The impactabsorber made of low repulsive rubber may be used as a material of eachdamper 44, 44 similarly as for the above mentioned damper 7, 8. Bearing43, 43 such as a ball bearing is fit in the bearing holder 45, 45through each damper 44, 44, and a shaft 41 is rotatably supported by thebearing 43, 43. The shaft 41 is supported on the upper side of the abovementioned shaft 25 in a direction perpendicular to the shaft 25. Theshaft 41 suspends the light source unit holder 4 which is swingablearound the shaft 41. The above mentioned bearing 23, 43, the shaft 25,41, and the middle swinging frame 40 constitutes the gimbal mechanism 3,through which the support 2 swingably suspends the light source unitholder 4. The above mentioned shaft 25 penetrates the light source unitholder 4 and a relief hole 46 for the shaft 25 is formed in the lightsource unit holder 4 so that the shaft 25 does not obstruct the lightsource unit holder 4 swiging around the shaft 41.

A light source unit 5 is mounted on the upper end portion of the lightsource unit holder 4 and a light source unit 6 is mounted in the middleportion in vertical direction and under the above mentioned shaft 25.The light source unit 5 irradiates vertical line light and includes aunit case 51 and a rod lens 52 mounted on the upper end of the unit case51. A semiconductor laser is mounted as a light source in the unit case51 and a collimating lens for collimating diffusion light radiated fromthe semiconductor into parallel light flux is mounted. In theconfiguration, the above mentioned parallel light flux enters in adirection perpendicular to the center axis line with respect to the rodlens 52, and the rod lens 52 diffuses and outputs the parallel lightflux only in a direction perpendicular to the center axis line. When thelight source unit holder 4 is in the predetermined hanging position, therod lens 52 of the light source unit 5 is in a horizontal direction anddesigned to irradiate the vertical light line. The light source unit 5is configured to be mounted pointing obliquely upwards on the lightsource unit holder 4 to irradiate the line light from walls to ceilingsof the building for example.

The other light source unit 6 irradiates horizontal line light andincludes a unit case 61 and a rod lens 62 mounted to the end of thisunit case 61. The unit case 61 is provided with semiconductor laser as alight source and a collimating lens for collimating diffused lightradiated from the semiconductor laser into parallel light flux. In theconfiguration, the above mentioned parallel light flux enters indirection parallel to the center axis line with respect to the rod lens62 and the rod lens 62 diffuses and outputs the parallel light flux in adirection perpendicular to the center axis line. When the light sourceunit holder 4 is in the predetermined hanging position, the light sourceunit 6 is mounted pointing horizontal direction and the rod lens 62 ofthe light source unit 6 is oriented in vertical direction to irradiatehorizontal line light.

The light source unit holder 4 is provided with a braking plate 42 inthe lower end portion. The braking plate 42 is to brake swing of thelight source unit holder 4 due to magnetic action, and formed in suchway that a swing direction with the above mentioned shaft 25 as a centerforms in an arc following a swing trait and formed to extend 7 to bothsides of the light source unit holder 4. A swing direction of the abovementioned braking plate 42 with the above mentioned shaft as a center isformed in an arc following the swing trait. Material of the light sourceunit holder 4 is not particularly specified but at least a portion ofthe braking plate 42 is formed of conductive material. The upper face ofthe bottom plate 26 of the above mentioned support 2 is fixed with theappropriate number of magnets 50 appropriately spaced with respect tothe above mentioned braking plate 42. Each magnet 50 is arranged throughappropriate yoke in such way that the magnet 50 is declined to cope withthe arc face of the braking plate 42 to correspond the above mentionedbraking plate 42 with the arc face. The braking plate 42 is locatedwithin magnetic field formed by respective magnets 50. When the lightsource unit holder 4 is swung by the gimbal mechanism 3, the brakingplate 42 crosses the line of magnetic force of the magnetic field togenerate eddy current to the braking plate 42. With this eddy current,driving force (torque) is generated in a direction opposite to the swingdirection of the light source unit holder 4. Therefore, this drivingforce functions as a force to stop the swing of the light source unitholder 4, and quickly stop the light source unit holder 4.

Thus the configuration of the embodiment shown in the drawings wasdescribed. Next, action and effect of the above mentioned embodimentwill be described. It is assumed that the marking device is applied withexterior impact for some factors such as dropping or falling down. Asmentioned above, with regard to the vertical impact force, the largediameter portions in the both ends in vertical direction of dampers 7, 8in the upper portion and the lower portion are deformed, thereby thedampers 7, 8 converts impact force into thermal energy to reduce impactforce transmitted from the housing 1 to the support 2. With respect tohorizontal impact force, small diameter portion of the dampers 7, 8 inthe upper and the lower portion is pushed by a bent piece 91 of theextension mount member 9 and the deformation of each small diameterportion converts the impact force to reduce the impact force to betransmitted from the housing 1 to the support 2. Since the support 2 ismounted in such way that the upper portion and the lower portion of thesupport 2 are raised from the housing 1 due to interference of thedampers 7 and 8, the outside impact force is absorbed by respectivedampers 7, 8, thereby the impact force transmitted from the housing tothe support 2 can be dramatically reduced. The impact force applied tothe gimbal mechanism 3 supporting the support 2 can be also reduced,damage to the gimbal mechanism caused by the outside impact force can bereduced, and accuracy distortion caused by the impact force applied tothe marking device can be dramatically reduced. Therefore, it is durableeven for rough handling, can be continuously used without readjustmentor repair even if relatively big impact force is applied, and chances ofreadjustment or repair can be reduced.

An object of the present invention can be achieved by coupling the upperportion and the lower portion of the support 2 with the housing 1through dampers 7 and 8 made of impact absorber. In addition to this,the shafts 25 and 41 constituting the gimbal mechanism 3 are supportedthrough the dampers 22 and 44 as in the embodiment in the drawing sothat damage applied to the shafts 25 and 41 of the gimbal mechanism 3caused by outside impact force can be further efficiently reduced. Anddistortion of the accuracy due to the impact force can be efficientlyreduced and chances of readjustment and maintenance can be reduced.

The damage applied to the shafts 25 and 41 of the gimbal mechanism 3includes deformation of the bearing supporting the shafts 25 and 41 aswell as bent and deformation of the shafts 25 and 41. When the shafts 25and 41 of the gimbal mechanism 3 subject to damage, the gimbal mechanism3 does not operate smoothly and the light source unit holder 4 can nothold the predetermined hanging position, thereby causing uneven staticposition of the light source unit holder 4. As a result, line lightsirradiated from the light source units 5 and 6 is not in verticaldirection or horizontal direction.

With this respect, with the present invention, since damage of the shaftof the gimbal mechanism due to the impact force can be reduced furtherefficiently, distortion of degree of the vertical line light and thehorizontal line light can be prevented even if relatively big impactforce is applied.

Although two dampers are provided respectively with regard to dampers 7and 8 in the upper portion and the lower portion in the embodiment inthe drawing, the number of dampers in the upper and lower portions isarbitrary. For example, in the upper portion and the lower portion, aplurality of dampers may be arranged in one portion and a single dampermay be arranged in the other portion. Further, three dampers may bearranged at least one portion and the dampers may be supported bysupport at three points.

As shown in the embodiment of the drawing, the upper portion and thelower portion each has a pair of dampers, and dampers are arranged insuch way that a line connecting centers of two dampers in the upperportion and a line connecting centers of two dampers in the lowerportion are perpendicular with each other. Then the support is preventedfrom declining in one side and the support can be stably supported.

1. A marking device comprising: a support mounted inside a housing; alight source unit holder swingably suspended by said support through agimbal mechanism; and a light source unit mounted on this light sourceunit holder so as to diffuse a light flux only in a single direction toradiate line light; wherein said support is coupled with said housingthrough dampers and the dampers in upper portion and lower portion areformed of impact absorber, and when outside impact is applied, saiddamper absorbs impact energy to prevent the impact force fromtransmitting to said support.
 2. The marking device according to claim1, wherein said damper comprises a hole in an axis direction and a smalldiameter portion in a middle portion in an axis direction, one end ofsaid hole is penetrated by a mounting shaft coupled with the housing orthe support and the damper is coupled with said support, and said smalldiameter portion is fit in with a portion substantially integrated withsaid support or housing so that an upper portion and an lower portion ofthe support are coupled with the housing through the dampers.
 3. Themarking device according to claim 2, wherein the damper absorbs avertical impact force of the marking device at both ends in axialdirection and a horizontal impact force of the marking device at thesmall diameter portion in the middle portion in an axial direction. 4.The marking device according to claim 1, wherein dampers in the upperportion and the lower portion each are in pair, and a line connectingcenters of two dampers in the upper portion is mutually perpendicular toa line connecting centers of two dampers in the lower portion.
 5. Themarking device according to claim 1, wherein one of the upper portionand the lower portion is arranged with a plurality of dampers and theother portion is arrange with a single damper.
 6. The marking deviceaccording to claim 1, wherein at least one of the upper portion and thelower portion is arranged with three dampers and supports the support atthree points.
 7. The marking device according to claim 1, whereinmaterials of the damper are different between both end sides in axialdirection and the small diameter portion in the middle portion in axialdirection.
 8. The marking device according to claim 1, wherein shaftsconstituting the gimbal mechanism, at least shafts supported by thesupport are supported by said support through impact absorbing damperscovering the both end portions.
 9. The marking device according to claim2, wherein a mounting member is fixed inside periphery of the bottomportion of the housing, this mounting member is fit in with the smalldiameter portion of the lower damper, and the lower portion of thesupport is coupled with the housing through the damper.
 10. The markingdevice according to claim 2, wherein the upper portion of the support isextended with an extension mounting member, this mounting member is fitin with the small diameter portion of the upper damper and the upperportion of the support is coupled with the housing through the damper.11. The marking device according to claim 2, wherein a sleeve is fit inthe hole of the damper in axial direction and a mounting shaftpenetrates the hole.